%0 Journal Article %J Physical Review Letters %D 2013 %T Quantum Catalysis of Magnetic Phase Transitions in a Quantum Simulator %A Philip Richerme %A Crystal Senko %A Simcha Korenblit %A Jacob Smith %A Aaron Lee %A Rajibul Islam %A Wesley C. Campbell %A Christopher Monroe %X We control quantum fluctuations to create the ground state magnetic phases of a classical Ising model with a tunable longitudinal magnetic field using a system of 6 to 10 atomic ion spins. Due to the long-range Ising interactions, the various ground state spin configurations are separated by multiple first-order phase transitions, which in our zero temperature system cannot be driven by thermal fluctuations. We instead use a transverse magnetic field as a quantum catalyst to observe the first steps of the complete fractal devil's staircase, which emerges in the thermodynamic limit and can be mapped to a large number of many-body and energy-optimization problems. %B Physical Review Letters %V 111 %8 2013/9/5 %G eng %U http://arxiv.org/abs/1303.6983v2 %N 10 %! Phys. Rev. Lett. %R 10.1103/PhysRevLett.111.100506